SMT4214 Summit Microelectronics, Inc., SMT4214 Datasheet - Page 7

• Manufacturer Part Number: SMT4214
• Description: Expandable Four-rail Supply TRAKKER™ Controller
• Manufacturer: Summit Microelectronics, Inc.

PACKAGE PIN CONFIGURATION
PIN DESCRIPTIONS CONT’D
Summit Microelectronics, Inc
Number
Pin
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Type
PWR
PWR
Pin
I/O
I/O
O
O
O
O
O
I
I
I
I
I
VDD_CAP
Pin Name
VGATED
VGATEC
VGATEB
VGATEA
VRLINK
LINK#
IRQ#
GND
SCL
VI
VI
VI
VI
B
C
D
A
P W R _O N #
IR Q _C L R #
V G G _ C AP
S EAT E D #
Interrupt is an active low open-drain output. It can be programmed so that it is
driven low on an under-voltage condition. It is cleared by removing any under-
voltage conditions and asserting IRQ_CLR#.
VDD_CAP is a charge storage connection to the SMT4214’s internal power
supply. For most applications this is tied to a 10µF capacitor. A smaller 0.1µF
can be added in parallel for additional noise decoupling
The VGATE outputs are used to control the “turn-on” of the card-side voltages by
providing a high side voltage to a power MOSFET. The VGATE output voltages
are programmable as either 10.5V or 14.5V depending on the type of Mosfet gate
drive needed to fully enhance the device. See Figure 8 for additional external
component recommendations.
Voltage Ramp Link is an I/O and is used in a multi-SMT4214 application. If the
SMT4214 is designated as the master its VRLINK will become an output
providing the ramp reference of the card-side voltages for the slave SMT4214’s.
If the SMT4214 is designated as a slave its VRLINK will become the input for the
VRLINK of the master.
Link is an active low open-drain I/O internally connected to VDD_CAP through a
100kΩ pull-up resistor. In a multi-SMT4214 application the LINK# pin of all the
devices can be tied together to synchronize tracking. The LINK# I/O is active only
during a power-on or power-off operation. If one of the devices is falling behind in
tracking of the card-side voltage, it will assert its LINK# output and temporarily
halt the ramping of the VGATE voltages of the other devices.
The Voltage Inputs provide two functions. Internally they are diode-OR’ed;
therefore, the input with the highest voltage will act as the device’s VDD supply.
They are also the bus-side (unswitched) voltage monitoring inputs to the
individual supply managers. . See Figure 8 for additional external component
recommendations.
GND is the ground for both the analog and digital portions of the internal circuitry.
SCL is the serial clock input, used for clocking data into or out of the SMT4214.
SCL is internally connected to VDD through a 100kΩ pull-up resistor. In multiple
device systems, an external pull-up should be connected to the highest supply.
R S T #
M R #
S D A
F S #
V O
V O
V O
V O
A0
A1
C
D
B
A
P IN 1
28 Lead SSOP
SM T4214
2061 1.0 8/16/02
15
Pin Description
L IN K #
S C L
G N D
V R L IN K
V G AT E
V G AT E
V G AT E
V D D _C AP
IR Q #
V I
V I
V I
V I
V G AT E
D
C
B
A
A
B
C
D
Preliminary Information
SMT4214
7